US9421592B2 - Asymmetric rolling device, asymmetric rolling method and rolled material manufactured using same - Google Patents

Asymmetric rolling device, asymmetric rolling method and rolled material manufactured using same Download PDF

Info

Publication number
US9421592B2
US9421592B2 US13/635,900 US201113635900A US9421592B2 US 9421592 B2 US9421592 B2 US 9421592B2 US 201113635900 A US201113635900 A US 201113635900A US 9421592 B2 US9421592 B2 US 9421592B2
Authority
US
United States
Prior art keywords
rolling
roll
rolls
asymmetric
rolling material
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active, expires
Application number
US13/635,900
Other languages
English (en)
Other versions
US20130017118A1 (en
Inventor
Hyo-Tae JEONG
Byung-Hak CHOE
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Solum Advanced Materials Co Ltd
Original Assignee
Industry Academy Cooperation Foundation of Gangneung Wonju National University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Industry Academy Cooperation Foundation of Gangneung Wonju National University filed Critical Industry Academy Cooperation Foundation of Gangneung Wonju National University
Assigned to Gangneung-Wonju National University Industry Academy Cooperation Group reassignment Gangneung-Wonju National University Industry Academy Cooperation Group ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: CHOE, BYUNG-HAK, JEONG, HYO-TAE
Publication of US20130017118A1 publication Critical patent/US20130017118A1/en
Application granted granted Critical
Publication of US9421592B2 publication Critical patent/US9421592B2/en
Assigned to SOLUM HOLDINGS CO., LTD. reassignment SOLUM HOLDINGS CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: GANGNUNG-WONJU NATIONAL UNIVERSITY INDUSTRY ACADEMY COOPERATION GROUP
Assigned to SOLUM ADVANCED MATERIALS CO., LTD. reassignment SOLUM ADVANCED MATERIALS CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SOLUM HOLDINGS CO., LTD.
Active legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
    • B21B27/02—Shape or construction of rolls
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2265/00—Forming parameters
    • B21B2265/24—Forming parameters asymmetric rolling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2267/00—Roll parameters
    • B21B2267/02—Roll dimensions
    • B21B2267/06—Roll diameter
    • B21B2267/065—Top and bottom roll have different diameters; Asymmetrical rolling

Definitions

  • the present invention relates to a rolling technology used to form a metal into a rolled material, and more particularly, to a rolling technology for improving formability or other physical properties of a rolled material by controlling texture of the rolled material.
  • rolling is performed to process a metal into a sheet having a certain size.
  • the volume of a rolling material changes and thus microstructures of the rolling material also change.
  • microstructures of a rolling material change, the rolling material has texture in which crystals are oriented in a particular direction. Texture formed due to rolling is closely related to formability of a rolling material. Accordingly, by controlling texture of a rolling material in a rolling process, formability of the rolling material after being rolled may be improved.
  • the present invention provides a rolling method capable of providing a high formability to a rolled material by controlling texture of the rolled material.
  • the present invention also provides a rolled material having a formability improved by performing the rolling method.
  • the present invention also provides a rolling apparatus for performing the rolling method.
  • an asymmetric rolling method including disposing a rolling material having first and second surfaces between a first roll and a second roll having a diameter greater than that of the first roll; and rolling the rolling material by adjusting power provided from a power providing unit to each of the first and second rolls to control angular velocities of the first and second rolls to be different from each other such that a shear strain applied by the first roll to one of the first and second surfaces of the rolling material is different from that applied by the second roll to the other of the first and second surfaces.
  • the rolling material may be rolled by maintaining linear velocities of the first and second rolls to be the same.
  • a linear velocity difference between the first and second rolls which is defined by Equation 1, may be equal to or less than 10%.
  • the rolling material may be rolled two or more times by allowing the first roll to apply a shear strain to the first surface and allowing the second roll to apply a shear strain to the second surface.
  • the rolling material may be rolled two or more times by switching surfaces of the rolling material, which receive shear strains from the first and second rolls, at least once.
  • the rolling material may be rolled two or more times in the same rolling direction.
  • the rolling material may be rolled two or more times by changing rolling directions of the rolling material at least once.
  • a third roll having a diameter greater than that of the first roll may be coupled to the first roll to support the first roll at a side opposite to the second roll.
  • an asymmetric rolling method for rolling a rolling material by using at least one pair of working rolls with different diameters and controlled to rotate at the same linear velocity by power provided by a power providing unit.
  • An asymmetric rolling method may be performed a plurality of times, and the plurality of times may include turning the rolling material upside down at least once between passes.
  • An asymmetric rolling method may be performed a plurality of times, and the plurality of times may include changing rolling directions of the rolling material at least once between passes.
  • a backup roll for supporting one of the working rolls, which has a relatively small diameter, may be coupled to the one of the working rolls at a side opposite to the other of the working rolls, which has a relatively large diameter.
  • a rolled material manufactured by using the above asymmetric rolling method.
  • the rolled material may have a hexagonal close-packed (HCP) crystal structure.
  • the rolled material may include magnesium (Mg), an Mg alloy, titanium (Ti), or a Ti alloy.
  • the rolled material may include aluminum (Al), an Al alloy, or an iron-silicon (Fe—Si) alloy.
  • an asymmetric rolling apparatus including a first roll contacting a first surface of a rolling material; a second roll having a diameter different from that of the first roll and contacting a second surface of the rolling material opposite to the first surface; and a power providing unit for providing power to each of the first and second rolls so as to adjust linear velocities of the first and second rolls to be the same.
  • the power providing unit may control linear velocities of the first and second rolls to be the same.
  • the power providing unit may include first and second motors for respectively driving the first and second rolls; and a motor control unit for controlling angular velocities of the first and second motors.
  • the asymmetric rolling apparatus may further include a first gear coupled to the first roll and a second gear coupled to the second roll, wherein the second gear is coupled to the first gear with a gear ratio different from that of the first gear, and the power providing unit may include a motor for providing driving power to the first or second gear.
  • the asymmetric rolling apparatus may further include a third roll having a diameter greater than that of the first roll and coupled to the first roll to support the first roll at a side opposite to the second roll.
  • the power providing unit may include a first motor for driving the first or third roll, a second motor for driving the second roll, and a motor control unit for controlling angular velocities of the first and second motors.
  • the asymmetric rolling apparatus may further include a first gear coupled to the first or third roll and a second gear coupled to the second roll, wherein the second gear is coupled to the first gear with a gear ratio different from that of the first gear, and the power providing unit may include a motor for providing driving power to the first or second gear.
  • the first or second gear may be a variable gear for changing at least one gear ratio
  • the asymmetric rolling apparatus may further include a gear control unit for controlling the gear ratio
  • a rolling method and apparatus may produce rolled material with improved formability compared to conventional systems.
  • a metallic material having a poor formability at room temperature such as a magnesium (Mg) alloy
  • slip systems may be oriented in such a way that shear strains are easily received even at room temperature.
  • an excellent formability at room temperature may be achieved.
  • FIGS. 1A and 1B are a front view of and a perspective view of a rolling apparatus according to an embodiment of the present invention.
  • FIGS. 2A and 2B are a front view of and a perspective view of a rolling apparatus according to another embodiment of the present invention.
  • FIG. 3 is a front view of a rolling apparatus according to another embodiment of the present invention.
  • FIG. 4 shows slip systems of magnesium (Mg) having a hexagonal close-packed (HCP) crystal structure.
  • FIG. 5 shows orientations of HCP crystals of a rolling material.
  • FIG. 6 shows poles of crystals A, B, C, and D illustrated in FIG. 5 , on the (0001) pole figure.
  • FIG. 7 shows the (0001) pole figures of an AZ31 alloy rolled by using a rolling method according to an embodiment of the present invention.
  • FIGS. 8 through 10 show the (0001) pole figures of an AZ31 alloy rolled by using rolling methods according to comparative examples.
  • FIG. 11 is a diagram for describing a rolling method according to another embodiment of the present invention.
  • FIG. 12 shows the (0001) pole figure of an AZ31 alloy rolled by using the rolling method illustrated in FIG. 11 .
  • FIG. 13 is a diagram for describing a rolling method according to another embodiment of the present invention.
  • FIG. 14 shows the (0001) pole figures of an AZ31 alloy rolled by using the rolling method illustrated in FIG. 13 .
  • a rolling apparatus and a rolling method, according to embodiments of the present invention may be applied to any rolling material in order to improve formability of the rolling material, and the following embodiments exemplarily show the concept of the present invention.
  • the term “texture” may refer to the crystalline orientation of a polycrystalline material.
  • the term “texture” does not limit the scope of the present invention.
  • the texture of a material is used as a relative concept rather than an absolute concept. That is, if a material has texture in a predetermined direction, it means that most, not all, of crystalline grains of the material have texture in the mentioned direction.
  • a pole figure may be a figure showing a distribution of the direction of crystallographic lattice planes in the form of stereographic projection to show the orientation or texture of crystals of a material.
  • the pole figure may be created by using X-ray diffraction (XRD).
  • a rolling material refers to a target material to be rolled
  • a rolled material refers to a resultant material obtained by rolling the rolling material
  • FIGS. 1A and 1B illustrate a rolling apparatus 100 according to an embodiment of the present invention.
  • FIG. 1A is a front view of the rolling apparatus 100
  • FIG. 1B is a perspective view of first and second rolls 101 and 102 , and a rolling material 104 of the rolling apparatus 100 illustrated in FIG. 1A .
  • the rolling apparatus 100 is an asymmetric rolling apparatus in which the first and second rolls 101 and 102 have different diameters.
  • the exemplary rolling apparatus 100 includes the first roll 101 contacting a first surface 104 a of the rolling material 104 , the second roll 102 having a diameter greater than that of the first roll 101 and contacting a second surface 104 b of the rolling material 104 opposite to the first surface 104 a , and a power providing unit 105 for providing power to each of the first and second rolls 101 and 102 to separately adjust angular velocities of the first and second rolls 101 and 102 .
  • the first and second rolls 101 and 102 are oriented as upper and lower rolls in the embodiment shown in FIGS. 1A and 1B , other embodiments are also available. Also, for convenience of explanation, a surface contacting the first roll 101 that is the upper roll is shown as the first surface 104 a , and a surface contacting the second roll 102 that is the lower roll is shown as the second surface 104 b . Accordingly, if the rolling material 104 is turned upside down, the first roll 101 contacts the second surface 104 b of the rolling material 104 , and the second roll 102 contacts the first surface 104 a of the rolling material 104 .
  • the first and second rolls 101 and 102 are oriented in parallel and are spaced apart from a supporting plate 110 , and are mounted between frames 111 fixed by a coupling member 112 such as a screw.
  • the power providing unit 105 may include first and second motors 106 and 107 for respectively driving the first and second rolls 101 and 102 , and a motor control unit 108 for controlling angular velocities of the first and second motors 106 and 107 .
  • first and second motors 106 and 107 transfer rotatory power to the first and second rolls 101 and 102 via connection members 109 .
  • the motor control unit 108 may control the angular velocities of the first and second rolls 101 and 102 connected to or coupled to the first and second motors 106 and 107 by controlling the angular velocities of the first and second motors 106 and 107 , and thus may control linear velocities of the first and second rolls 101 and 102 .
  • the relationship between angular velocity and linear velocity can be represented by multiplying angular velocities of the first and second rolls 101 and 102 by radiuses of the first and second rolls 101 and 102 .
  • a first shear strain applied by the first roll 101 to the first surface 104 a of the rolling material 104 may be controlled to be different from a second shear strain applied by the second roll 102 to the second surface 104 b of the rolling material 104 .
  • the motor control unit 108 may control the first and second rolls 101 and 102 to roll the rolling material 104 by rotating the first and second rolls 101 and 102 to have the same linear velocity. That is, the linear velocities of the first and second rolls 101 and 102 may be the same by controlling a ratio between the angular velocities of the first and second rolls 101 and 102 to be the same as the inverse of the ratio between the radiuses of the first and second rolls 101 and 102 .
  • linear velocities have been described as being the same, the term “the same” should be regarded as substantial sameness including complete sameness and sameness within a process margin caused by an error that occurs due to process variations even when a user controls signals of the motor control unit 108 with an intention of controlling the angular velocities of the first and second rolls 101 and 102 to be the same.
  • the “sameness” between the linear velocities of the first and second rolls 101 and 102 is also applied to the following descriptions.
  • a third roll 103 having a diameter greater than that of the first roll 101 , and coupled to the first roll 101 to support the first roll 101 at a side opposite to the second roll 102 may be further included.
  • the first and second rolls 101 and 102 may function as working rolls that contact and directly apply shear strains to the first and second surfaces 104 a and 104 b of the rolling material 104
  • the third roll 103 may function as a backup roll that helps the first roll 101 to be balanced against an external force applied in a rolling process from the second roll 102 having a diameter greater than that of the first roll 101 .
  • a power providing unit 105 may include the first motor 106 for driving the first or third roll 101 or 103 , the second motor 107 for driving the second roll 102 , and the motor control unit 108 for controlling the angular velocities of the first and second motors 106 and 107 .
  • the first motor 106 is coupled to the third roll 103 and transfers driving power to the third roll 103 . If the third roll 103 rotates, the first roll 101 contacting the third roll 103 may also rotate due to friction. Although not shown in FIGS. 2A and 2B , the first motor 106 may be connected to or coupled to the first roll 101 to allow the first roll 101 to rotate, and the third roll 103 may rotate due to friction according to the above-described principle.
  • the rolling apparatus 100 including the first through third rolls 101 through 103 may include a first gear 114 coupled to the first or third roll 101 or 103 , and a second gear 115 coupled to the second roll 102 , wherein the second gear 115 is coupled to the first gear 114 with a predetermined gear ratio, and the power providing unit 105 may include a motor 113 for transferring driving power to the first or second gear 114 or 115 .
  • a motor 113 may be directly connected to and may directly transfer power to the first or second gear 114 or 115 without using the driving gear 116 .
  • the embodiment of the rolling apparatus 100 shown in FIG. 3 includes the third roll 103 as a support roll, in embodiments where only the first and second rolls 101 and 102 are included without including the third roll 103 , the first and second gears 114 and 115 may be respectively connected to the first and second rolls 101 and 102 as described above.
  • first or second gear 114 or 115 may be a geared for variably changing at least one gear ratio
  • a gear control unit 117 coupled to the first or second gear 114 or 115 which may be configured for controlling the gear ratio may be further included.
  • the linear velocities of the first and second rolls 101 and 102 may be controlled by adjusting the gear ratios of the first and second gears 114 and 115 in consideration of the diameters of the first and second rolls 101 and 102 .
  • power generated by the motor 113 may be transferred so that the first and second rolls 101 and 102 have the same linear velocity according to the gear configurations described above.
  • the gear ratios of the first and second gears 114 and 115 may be variably controlled by using the gear control unit 117 in consideration of the diameter of the first or second roll 101 or 102 , and thus the linear velocities of the first and second rolls 101 and 102 may be controlled to be the same.
  • a rolling method according to an embodiment of the present invention may include rolling a rolling material by using at least one pair of working rolls including rolling rolls having different diameters.
  • the rolling material 104 to be rolled by the above-described asymmetric rolling apparatus 100 may include magnesium (Mg) or a Mg alloy having a hexagonal close-packed (HCP) crystal structure.
  • Mg which typically has a density of 1.74 g/cm 3 has a low weight and excellent specific strength and specific modulus in comparison to iron (Fe) which typically has a density of 7.90 g/cm 3 or aluminum (Al) which typically a density of 2.7 g/cm 3 .
  • Fe iron
  • Al aluminum
  • Mg due to high absorption of vibration, impact, electromagnetic waves, etc. and excellent electric and thermal conductivities, Mg is used as a lightweight material in motor vehicles, aircraft, etc. and is also used in electronic fields of mobile phones, laptop computers, etc.
  • Mg having a HCP crystal structure has poor slip systems and thus has a low formability at room temperature. That is, as illustrated in FIG. 4 , during formation, a basal plane slip system of ⁇ 0001 ⁇ 1120>, a prismatic slip system of ⁇ 1010 ⁇ 1120>, a pyramidal slip system of ⁇ 1011 ⁇ 1120>, etc. are mainly used as deformation mechanisms of Mg. However, since critical resolved shear stress values of the basal plane slip system are substantially lower than values for other mechanisms at room temperature, the orientation of the basal plane slip system within the rolling material has a great influence on room temperature formability.
  • the basal plane slip system is tilted by a certain angle with respect to a main deformation direction as represented by crystal D in FIG. 5 , the basal slip plane is oriented to facilitate deformation, and an excellent formability at room temperature is achieved.
  • the orientation and distribution of the basal plane slip systems in a material may be characterized as illustrated in the (0001) pole figure of FIG. 6 .
  • FIG. 6 shows how poles of the crystals A, B, C, and D illustrated in FIG. 5 would appear on an (0001) pole figure.
  • an asymmetric rolling method may include disposing the rolling material 104 having the first and second surfaces 104 a and 104 b between the first and second rolls 101 and 102 , and rolling the rolling material 104 by adjusting angular velocities of the first and second rolls 101 and 102 to be different from each other such that a shear strain applied by the first roll 101 to one of the first and second surfaces 104 a and 104 b of the rolling material 104 , for example, the first surface 104 a , is different from that applied by the second roll 102 to the other of the first and second surfaces 104 a and 104 b , for example, the second surface 104 b.
  • the rolling material 104 may be rolled by maintaining, for example, linear velocities of the first and second rolls 101 and 102 to be the same.
  • the rolling material 104 may include an AZ31 alloy as an Mg alloy. Although embodiments are not limited thereto, in the following description, the rolling material 104 is assumed as an AZ31 alloy.
  • an asymmetric rolling method includes a method of rolling the rolling material a plurality of times.
  • the above rolling method may be used to prevent a problem caused when a large reduction ratio is applied to a rolling material, by repeatedly applying appropriately predetermined reduction ratios to the rolling material.
  • the plurality of times refers to a total number of times that a rolling material is rolled by working rolls.
  • a rolling material may be rolled a plurality of times by reinserting the material through the same set of working rolls, or by inserting the rolling material into a plurality of pairs of working rolls arranged in series in a continuous process.
  • Embodiments of the present invention include continuous insertion and intermittent insertion of the rolling material between the working rolls.
  • a method of rolling a plurality of times may include reinsertion of the rolling material after being physically released from the working rolls, and reinsertion of the rolling material between the working rolls by allowing the working rolls to rotate in reverse while the rolling material is still disposed between the working rolls.
  • each of the plurality of times that rolling is performed may be referred to as a “pass”.
  • FIG. 7 shows the (0001) pole figures of an AZ31 alloy rolled five times by using the rolling apparatus 100 illustrated in FIGS. 2A and 2B and by controlling the first and second rolls 101 and 102 to have the same linear velocity.
  • a reduction ratio of the AZ31 alloy was 75%
  • a rolling temperature was 300° C.
  • Rolling was performed in the same rolling direction by allowing the first and second surfaces 104 a and 104 b of the rolling material 104 , i.e., the AZ31 alloy, to respectively contact and receive shear strains from the first and second rolls 101 and 102 .
  • FIG. 7 shows the (0001) pole figures of an AZ31 alloy rolled five times by using the rolling apparatus 100 illustrated in FIGS. 2A and 2B and by controlling the first and second rolls 101 and 102 to have the same linear velocity.
  • a reduction ratio of the AZ31 alloy was 75%
  • a rolling temperature was 300° C.
  • Rolling was performed in the same rolling direction by allowing the first and second surfaces 104
  • a lower figure is the (0001) pole figure of the first surface 104 a that received a shear strain from is the first roll 101
  • an upper figure is the (0001) pole figure of the second surface 104 b that received a shear strain from the second roll 102 .
  • an orientation of a basal plane, i.e., the (0001) plane, of HCP crystal is out of center.
  • a rotation angle i.e., an angle from the center
  • a rotation angle of a pole point of the basal plane with respect to the first surface 104 a that received a shear strain from the first roll 101 was about 15°
  • a rotation angle of a pole point of the basal plane with respect to the second surface 104 b that received a shear strain from the second roll 102 was about 6°.
  • FIGS. 8 through 10 show the (0001) pole figures of an AZ31 alloy rolled by using a conventional rolling apparatus including working rolls having the same diameter.
  • FIGS. 8A through 8C show the (0001) pole figures of the AZ31 alloy rolled a plural number of times to a reduction ratio of 75% at a rolling temperature of 300° C. by allowing first and second surfaces of a rolling material, i.e., the AZ31 alloy, to respectively contact and receive shear strains from first and second rolls.
  • FIG. 8A shows the (0001) pole figure obtained when rolling with a reduction ratio of 10% was performed twelve times
  • FIG. 8B shows the (0001) pole figure obtained when rolling with a reduction ratio of 20% was performed six times
  • FIG. 8C shows the (0001) pole figure obtained when rolling with a reduction ratio of 30% was performed four times.
  • pole points have maximum polar strengths equal to greater than 10% and are all centered.
  • FIGS. 9A through 9C show the (0001) pole figures of the AZ31 alloy rolled at a rolling temperature of 200° C. In this case, reduction ratios were 50%, 30%, and 15% respectively. As illustrated in FIGS. 9A through 9C , pole points of a basal plane have maximum polar strengths equal to greater than 12% and are all centered.
  • a texture of an AZ31 alloy rolled according to an embodiment of the present invention may have an orientation capable of greatly improving formability.
  • FIGS. 10A through 10C show the (0001) pole figures of the AZ31 alloy rolled by using a conventional differential speed rolling method performed by rotating one of working rolls having the same diameter at a linear velocity greater than that of the other of the working rolls.
  • a ratio between linear velocities of the working rolls was maintained as 3:1
  • a rolling temperature was 200° C.
  • reduction ratios were 70%, 30%, and 15% respectively in FIGS. 10A through 10C .
  • lower figures are the (0001) pole figures of a surface that receives a shear strain from the fast roll
  • upper figures are the (0001) pole figures of a surface that receives a shear strain from the slow roll.
  • an AZ31 alloy rolled by using an asymmetric rolling method according to an embodiment of the present invention may have an orientation of crystals on a basal plane which is capable of greatly improving formability.
  • differential speed rolling is performed by using working rolls having the same diameter, since a rolling material slips due to a linear velocity difference between two rolls, shear strains may not be actually applied from rolling rolls to the rolling material. Also, the rolling material released out of the rolling rolls may be bent or may have rough surfaces.
  • an asymmetric rolling method according to an embodiment of the present invention since asymmetric shear strains due to different diameters of working rolls are applied using the same linear velocities, even though asymmetric rolling is performed, the rolling material may not slip. Also, defects such as bending or increased surface roughness of the rolling material, which occur in differential speed rolling, are not caused.
  • angular velocities of the first and second rolls 101 and 102 may be controlled with in a range in which a linear velocity difference defined by Equation 1 is equal to or less than 10%.
  • ⁇ 1 a linear velocity of the first roll 101
  • the rolling material released from the two rolling rolls may be bent due to, for example, an imbalance in stress.
  • Another embodiment of an asymmetric rolling method performed a plurality of times includes switching surfaces of the rolling material 104 , which receive shear strains from the first and second rolls 101 and 102 , at least once between passes.
  • the rolling material 104 is rolled in a first pass where the first and second surfaces 104 a and 104 b of the rolling material 104 to contact the first and second rolls 101 and 102 respectively. Subsequently, the rolling material 104 is turned upside down and is rolled in a second pass where the first and second surfaces 104 a and 104 b of the rolling material 104 contact the second and first rolls 102 and 101 , respectively.
  • upper and lower surfaces of rolling material 104 may be inverted in separate passes of a plurality of passes performed on the same rolling material.
  • two or more passes may be performed between the same pair of rolling rolls in a batch process, or may be performed between different pairs of rolling rolls corresponding to the passes.
  • the asymmetric shear strains due to different diameters of the first and second rolls 101 and 102 may be alternately applied to the first and second surfaces 104 a and 104 b , so that shear strains applied to each surface in the first and second passes may be normalized to a certain degree.
  • the number of times that rolling is performed may be two or more according to a desired reduction ratio.
  • Embodiments of the present invention are not limited by the particular number of times that the first and second surfaces 104 a and 104 b of the rolling material 104 are switched, or the number or order of passes that may be performed between switching
  • FIG. 12 shows an (0001) pole figure of an AZ31 alloy rolled at a rolling temperature of 300° C. in a total of five passes by switching rolling surfaces between each pass (a rolling reduction ratio was 75%).
  • a rotation angle of a basal plane is about 17°, which is greater than those of the (0001) pole figures illustrated in FIGS. 8 through 10 .
  • a rolling method includes rolling a plurality of times while changing rolling directions between passes.
  • a rolling direction of the rolling material 104 is set in such a way that the rolling material 104 is inserted between the first and second rolls 101 and 102 in direction A in a first pass.
  • the rolling direction of the rolling material 104 is turned by 180° so that the rolling direction is direction B while the first and second surfaces 104 a and 104 b are in the same orientation as the first pass.
  • FIG. 14 shows the (0001) pole figures of an AZ31 alloy rolled at a rolling temperature of 300° C. in a total of five passes while changing rolling directions between each pass (a rolling reduction ratio was 75%).
  • a lower figure is the (0001) pole figure of the first surface 104 a that received a shear strain from the first roll 101
  • an upper figure is the (0001) pole figure of the second surface 104 b that received a shear strain from the second roll 102 .
  • a rotation angle on the first surface 104 a that received a shear strain from the first roll 101 was about 5°
  • a rotation angle on the second surface 104 b that received a shear strain from the second roll 102 was about 17°.
  • the rotation angles are greater than those of the (0001) pole figures illustrated in FIGS. 8 through 10 .
  • embodiments of a method of performing rolling a plurality of times by changing rolling directions include reinserting the rolling material between the working rolls by allowing the working rolls to rotate in reverse while the rolling material is still disposed between the working rolls.
  • the above-described rolling apparatuses and rolling methods may be applied to any material for controlling texture of a rolled material.
  • a metallic material containing titanium (Ti) or a Ti alloy and having a HCP crystal structure, a metallic material containing Al or an Al alloy, or an iron-silicon (Fe—Si) alloy having magnetic properties influenced by an orientation of crystals of a rolled material may be used as a rolling material.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Metal Rolling (AREA)
  • Manufacturing Of Steel Electrode Plates (AREA)
US13/635,900 2010-03-18 2011-03-15 Asymmetric rolling device, asymmetric rolling method and rolled material manufactured using same Active 2032-10-07 US9421592B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
KR10-2010-0024299 2010-03-18
KR1020100024299A KR101084314B1 (ko) 2010-03-18 2010-03-18 비대칭 압연장치, 비대칭 압연방법 및 이를 이용하여 제조된 압연재
PCT/KR2011/001781 WO2011115402A2 (ko) 2010-03-18 2011-03-15 비대칭 압연장치, 비대칭 압연방법 및 이를 이용하여 제조된 압연재

Publications (2)

Publication Number Publication Date
US20130017118A1 US20130017118A1 (en) 2013-01-17
US9421592B2 true US9421592B2 (en) 2016-08-23

Family

ID=44649710

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/635,900 Active 2032-10-07 US9421592B2 (en) 2010-03-18 2011-03-15 Asymmetric rolling device, asymmetric rolling method and rolled material manufactured using same

Country Status (6)

Country Link
US (1) US9421592B2 (ko)
EP (1) EP2548663A4 (ko)
JP (2) JP5775888B2 (ko)
KR (1) KR101084314B1 (ko)
CN (1) CN103037992B (ko)
WO (1) WO2011115402A2 (ko)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11458518B2 (en) 2020-01-28 2022-10-04 Primetals Technologies Germany Gmbh Rolling mill with rolling dependent on material properties
US11642712B1 (en) * 2022-02-24 2023-05-09 GM Global Technology Operations LLC Method of manufacturing vehicle body structure component to include reinforced regions

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101274503B1 (ko) * 2011-03-28 2013-06-13 강릉원주대학교산학협력단 비대칭 압연장치, 비대칭 압연방법 및 이를 이용하여 제조된 압연재
KR101532646B1 (ko) * 2013-03-29 2015-06-30 한국기계연구원 대칭 및 비대칭 압연을 이용한 마그네슘 합금시트의 제조방법 및 이를 이용하여 제조된 마그네슘 합금시트
CN103978031B (zh) * 2014-03-25 2016-02-24 宁波宝新不锈钢有限公司 一种二十辊轧机的非对称轧制方法
US10023944B2 (en) 2014-04-01 2018-07-17 Honda Motor Co., Ltd. Compositions and integrated processes for advanced warm-forming of light metal alloys
CN105112832B (zh) * 2015-09-18 2017-03-22 上海交通大学 一种超细结构高强度Ti‑6Al‑4V合金板材的制备方法
CN106391700B (zh) * 2016-08-31 2018-02-09 燕山大学 一种下驱动式y型四辊板带轧机
KR101889019B1 (ko) 2016-12-23 2018-08-20 주식회사 포스코 마그네슘 합금판, 및 그 제조방법
CN108637015A (zh) * 2018-04-17 2018-10-12 河南明镁镁业科技有限公司 一种高效率环保异步轧机
CN112808772A (zh) * 2019-12-25 2021-05-18 中南大学 一种优化镁合金板材微观组织和力学性能的轧制成形方法

Citations (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1898061A (en) * 1929-09-27 1933-02-21 Allegheny Steel Co Treatment of electrical sheet steels
US2219665A (en) * 1937-05-19 1940-10-29 Simons Abraham Rolling mechanism
JPS53133555A (en) * 1977-04-27 1978-11-21 Ishikawajima Harima Heavy Ind Co Ltd Rolling method
JPS54110952A (en) 1978-02-21 1979-08-30 Ishikawajima Harima Heavy Ind Co Ltd Rolling method and apparatus
JPS54149351A (en) * 1978-05-17 1979-11-22 Ishikawajima Harima Heavy Ind Co Ltd Rolling method
JPS5550905A (en) * 1978-10-11 1980-04-14 Ishikawajima Harima Heavy Ind Co Ltd Rolling method with differential speed mill
US4269055A (en) * 1979-04-10 1981-05-26 Eugene W. Sivachenko Large profile sheet metal corrugator
US4299103A (en) * 1978-03-02 1981-11-10 Schloemann-Siemag Akt. Rolling mill
JPS56158205A (en) * 1980-05-07 1981-12-05 Nippon Steel Corp Asymmetrical rolling method
JPS5843808U (ja) 1981-09-17 1983-03-24 三菱重工業株式会社 ４重圧延機用減速機
US4406715A (en) * 1980-04-26 1983-09-27 Nippon Steel Corporation Process for producing grain-oriented electromagnetic steel strip
JPS59127912A (ja) * 1983-01-12 1984-07-23 Hitachi Ltd 圧延機
JPS603903A (ja) 1983-06-21 1985-01-10 Ishikawajima Harima Heavy Ind Co Ltd 圧延設備
JPS60108108A (ja) 1983-11-16 1985-06-13 Ishikawajima Harima Heavy Ind Co Ltd 圧延機のロ−ル駆動方法及び装置
US4566299A (en) * 1983-06-29 1986-01-28 Hitachi, Ltd. Control method and apparatus for rolling mill
US4625536A (en) * 1984-01-11 1986-12-02 Hitachi, Ltd. Method of controlling unequal circumferential speed rolling
US4781050A (en) * 1982-01-21 1988-11-01 Olin Corporation Process and apparatus for producing high reduction in soft metal materials
US4903518A (en) * 1986-10-13 1990-02-27 Hitachi, Ltd. Roll driving apparatus for rolling mill
JPH10296303A (ja) 1997-05-02 1998-11-10 Nippon Steel Corp 金属ストリップの圧延方法
JP2004306046A (ja) 2003-04-02 2004-11-04 Kawasaki Heavy Ind Ltd ５段圧延機および圧延機列ならびに圧延方法
JP2004311110A (ja) 2003-04-03 2004-11-04 Japan Storage Battery Co Ltd 蓄電池用格子の製造方法及び蓄電池
JP2005500164A (ja) 2001-08-24 2005-01-06 コラス・テクノロジー・ベー・ブイ 金属のスラブ、プレート又はストリップの処理用デバイス及びこのデバイスを使用して作られる製品
US20050172691A1 (en) * 2004-01-06 2005-08-11 Val Clecim Temper rolling machine of a metal band
JP2005298885A (ja) 2004-04-09 2005-10-27 Nippon Kinzoku Co Ltd 塑性加工性に優れたマグネシウム又はマグネシウム合金の板及びその製造方法
KR100718071B1 (ko) 2006-01-27 2007-05-14 주식회사 혁산압연 티타늄 이형압면체 제조방법
KR100775242B1 (ko) 2006-09-27 2007-11-12 주식회사 포스코 압연강판 선단부 휨발생 방지방법
WO2008105453A1 (ja) 2007-02-27 2008-09-04 Ngk Insulators, Ltd. 金属板材の圧延方法および前記圧延方法を用いて製造された圧延板材
US7546756B2 (en) * 2001-08-24 2009-06-16 Corus Technology Bv Method for processing a metal slab or billet, and product produced using said method
WO2009103436A1 (de) 2008-02-19 2009-08-27 Sms Siemag Ag Walzvorrichtung, insbesondere schubwalzengerüst
US8250895B2 (en) * 2007-08-06 2012-08-28 H.C. Starck Inc. Methods and apparatus for controlling texture of plates and sheets by tilt rolling

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4244203A (en) * 1979-03-29 1981-01-13 Olin Corporation Cooperative rolling process and apparatus
JPS5719106A (en) * 1980-07-10 1982-02-01 Nippon Steel Corp High screw down cold rolling mill
JPS57103721A (en) * 1980-12-18 1982-06-28 Nippon Steel Corp Stable rolling method for tri-star roll rolling mill
JPS5910403A (ja) * 1982-07-08 1984-01-19 Kawasaki Steel Corp 冷間タンデム圧延装置

Patent Citations (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1898061A (en) * 1929-09-27 1933-02-21 Allegheny Steel Co Treatment of electrical sheet steels
US2219665A (en) * 1937-05-19 1940-10-29 Simons Abraham Rolling mechanism
JPS53133555A (en) * 1977-04-27 1978-11-21 Ishikawajima Harima Heavy Ind Co Ltd Rolling method
JPS54110952A (en) 1978-02-21 1979-08-30 Ishikawajima Harima Heavy Ind Co Ltd Rolling method and apparatus
US4299103A (en) * 1978-03-02 1981-11-10 Schloemann-Siemag Akt. Rolling mill
JPS54149351A (en) * 1978-05-17 1979-11-22 Ishikawajima Harima Heavy Ind Co Ltd Rolling method
JPS5550905A (en) * 1978-10-11 1980-04-14 Ishikawajima Harima Heavy Ind Co Ltd Rolling method with differential speed mill
US4269055A (en) * 1979-04-10 1981-05-26 Eugene W. Sivachenko Large profile sheet metal corrugator
US4406715A (en) * 1980-04-26 1983-09-27 Nippon Steel Corporation Process for producing grain-oriented electromagnetic steel strip
JPS56158205A (en) * 1980-05-07 1981-12-05 Nippon Steel Corp Asymmetrical rolling method
JPS5843808U (ja) 1981-09-17 1983-03-24 三菱重工業株式会社 ４重圧延機用減速機
US4781050A (en) * 1982-01-21 1988-11-01 Olin Corporation Process and apparatus for producing high reduction in soft metal materials
JPS59127912A (ja) * 1983-01-12 1984-07-23 Hitachi Ltd 圧延機
JPS603903A (ja) 1983-06-21 1985-01-10 Ishikawajima Harima Heavy Ind Co Ltd 圧延設備
US4566299A (en) * 1983-06-29 1986-01-28 Hitachi, Ltd. Control method and apparatus for rolling mill
JPS60108108A (ja) 1983-11-16 1985-06-13 Ishikawajima Harima Heavy Ind Co Ltd 圧延機のロ−ル駆動方法及び装置
US4625536A (en) * 1984-01-11 1986-12-02 Hitachi, Ltd. Method of controlling unequal circumferential speed rolling
US4903518A (en) * 1986-10-13 1990-02-27 Hitachi, Ltd. Roll driving apparatus for rolling mill
JPH10296303A (ja) 1997-05-02 1998-11-10 Nippon Steel Corp 金属ストリップの圧延方法
US7546756B2 (en) * 2001-08-24 2009-06-16 Corus Technology Bv Method for processing a metal slab or billet, and product produced using said method
JP2005500164A (ja) 2001-08-24 2005-01-06 コラス・テクノロジー・ベー・ブイ 金属のスラブ、プレート又はストリップの処理用デバイス及びこのデバイスを使用して作られる製品
US20050034500A1 (en) 2001-08-24 2005-02-17 Van Der Winden Menno Rutger Device for processing a metal slab, plate or strip, and product produced using this device
JP2004306046A (ja) 2003-04-02 2004-11-04 Kawasaki Heavy Ind Ltd ５段圧延機および圧延機列ならびに圧延方法
JP2004311110A (ja) 2003-04-03 2004-11-04 Japan Storage Battery Co Ltd 蓄電池用格子の製造方法及び蓄電池
US20050172691A1 (en) * 2004-01-06 2005-08-11 Val Clecim Temper rolling machine of a metal band
JP2005298885A (ja) 2004-04-09 2005-10-27 Nippon Kinzoku Co Ltd 塑性加工性に優れたマグネシウム又はマグネシウム合金の板及びその製造方法
KR100718071B1 (ko) 2006-01-27 2007-05-14 주식회사 혁산압연 티타늄 이형압면체 제조방법
KR100775242B1 (ko) 2006-09-27 2007-11-12 주식회사 포스코 압연강판 선단부 휨발생 방지방법
WO2008105453A1 (ja) 2007-02-27 2008-09-04 Ngk Insulators, Ltd. 金属板材の圧延方法および前記圧延方法を用いて製造された圧延板材
US8250895B2 (en) * 2007-08-06 2012-08-28 H.C. Starck Inc. Methods and apparatus for controlling texture of plates and sheets by tilt rolling
WO2009103436A1 (de) 2008-02-19 2009-08-27 Sms Siemag Ag Walzvorrichtung, insbesondere schubwalzengerüst

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"Texture and microstructure changes in asymmetrically hot rolled AZ31 magnesium alloy sheets", Su-Hyeon Kim et al. published, Aug. 2005. *
International Search Report for PCT/KR2011/001781 filed on Mar. 15, 2011.

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11458518B2 (en) 2020-01-28 2022-10-04 Primetals Technologies Germany Gmbh Rolling mill with rolling dependent on material properties
US11642712B1 (en) * 2022-02-24 2023-05-09 GM Global Technology Operations LLC Method of manufacturing vehicle body structure component to include reinforced regions

Also Published As

Publication number Publication date
CN103037992A (zh) 2013-04-10
JP2015134378A (ja) 2015-07-27
JP5775888B2 (ja) 2015-09-09
EP2548663A2 (en) 2013-01-23
US20130017118A1 (en) 2013-01-17
KR101084314B1 (ko) 2011-11-16
WO2011115402A2 (ko) 2011-09-22
JP2013525111A (ja) 2013-06-20
KR20110105185A (ko) 2011-09-26
WO2011115402A3 (ko) 2012-02-23
EP2548663A4 (en) 2013-09-11
CN103037992B (zh) 2016-04-27

Similar Documents

Publication Publication Date Title
US9421592B2 (en) Asymmetric rolling device, asymmetric rolling method and rolled material manufactured using same
US9126248B2 (en) Asymmetric rolling apparatus, asymmetric rolling method and rolled materials fabricated by using the same
Deshpande et al. Effects of concentration-dependent elastic modulus on diffusion-induced stresses for battery applications
Zubar et al. Control of growth mechanism of electrodeposited nanocrystalline NiFe films
Yuasa et al. Effects of group II elements on the cold stretch formability of Mg–Zn alloys
Tang et al. Electrochemically driven phase transitions in insertion electrodes for lithium-ion batteries: examples in lithium metal phosphate olivines
Qi et al. Lithium concentration dependent elastic properties of battery electrode materials from first principles calculations
Huang et al. Dislocation based stress developments in lithium-ion batteries
Mizuno et al. Fabrication of LiCoO2 crystal layers using a flux method and their application for additive-free lithium-ion rechargeable battery cathodes
Uchiyama et al. Tin oxide meshes consisting of nanoribbons prepared through an intermediate phase in an aqueous solution
Kuroki et al. Seed-free fabrication of highly bi-axially oriented poly-Si thin films by continuous-wave laser crystallization with double-line beams
AlAmer et al. Continuous synthesis of structurally uniform graphene oxide materials in a model Taylor–Couette flow reactor
US20220152675A1 (en) Method for differential temperature rolling of composite strips based on actions of friction roller and device thereof
Bai et al. Communication—Fabrication of Vertical Nanotwinned Copper with (220) Texture by Direct Current Electrodeposition
Chun et al. The role of misorientation and coincident site lattice boundaries in Goss-textured Galfenol rolled sheet
KR101316724B1 (ko) 비대칭 압연장치, 비대칭 압연방법 및 이를 이용하여 제조된 압연재
Rahman et al. Room temperature control of grain orientation via directionally modulated current pulses
Luo et al. The Structure and micro-mechanical properties of electrodeposited cobalt films by micro-compression test
Chen et al. Predicting mechanical properties of polyvinylidene fluoride/carbon nanotube composites by molecular simulation
Go et al. Investigation of Stresses Generated during Lithium Transport through the RF Sputter-Deposited Li1− δ CoO2 Film by a DQCR Technique
Li et al. Formation and evolution of irregularly arranged prism-type Cu6Sn5 grains on electroplated (111) textured Cu
Terada et al. Effect of strain on “hardening by annealing and softening by deformation” phenomena in ultra-fine grained aluminum
Shimokawa et al. Grain subdivision mechanism related to partial disclinations in severe plastic deformation: a molecular dynamics study
Kitamura et al. Effect of rolling reduction on the deformation texture and anisotropy of transformation strain in Ti–50.2 at.% Ni thin plates
EP2192439A3 (en) Liquid crystal display and its manufacture method

Legal Events

Date Code Title Description
AS Assignment

Owner name: GANGNEUNG-WONJU NATIONAL UNIVERSITY INDUSTRY ACADE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:JEONG, HYO-TAE;CHOE, BYUNG-HAK;REEL/FRAME:029007/0590

Effective date: 20120913

STCF Information on status: patent grant

Free format text: PATENTED CASE

AS Assignment

Owner name: SOLUM HOLDINGS CO., LTD., KOREA, REPUBLIC OF

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:GANGNUNG-WONJU NATIONAL UNIVERSITY INDUSTRY ACADEMY COOPERATION GROUP;REEL/FRAME:044705/0840

Effective date: 20180110

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YR, SMALL ENTITY (ORIGINAL EVENT CODE: M2551); ENTITY STATUS OF PATENT OWNER: SMALL ENTITY

Year of fee payment: 4

AS Assignment

Owner name: SOLUM ADVANCED MATERIALS CO., LTD., KOREA, REPUBLIC OF

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SOLUM HOLDINGS CO., LTD.;REEL/FRAME:061583/0563

Effective date: 20221020

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YR, SMALL ENTITY (ORIGINAL EVENT CODE: M2552); ENTITY STATUS OF PATENT OWNER: SMALL ENTITY

Year of fee payment: 8